Hundreds of other victims die in less prominent overdoses each year in this state, where opioids such as heroin and fentanyl kill more people than car crashes.

Cassandra Nygren, 28, daughter of state Rep. John Nygren (R-Marinette), was in the Brown County Jail on Wednesday on expected charges of first-degree reckless homicide, delivery of heroin, child neglect and maintaining a drug trafficking place. Brown County Chief Deputy Todd Delain said Nygren could be charged as soon as Thursday.

Cassandra Nygren

Cassandra Nygren

Courtesy of Brown County Jail

In a separate case, Jason Sidener, 42, former executive director of the state Democratic Party, has not been arrested or charged but his home and car have been searched by police as part of a reckless homicide investigation into the death of a woman who overdosed in his Fitchburg condo.

Neither Sidener nor his attorney responded to messages Wednesday.

In a statement, state Democratic Party spokeswoman Melanie Conklin said that Sidener took medical leave in August, returned to work briefly in September and then left the job because his recovery would take longer than expected.

“We are cooperating fully with police and ask that everyone defer to their investigation out of respect for all those involved," Conklin said.

A search warrant shows Sidener drove a 30-year-old Madison woman to an emergency room on Sept. 12 when he suspected she had suffered an overdose. Monique Allen was dead when Sidener brought her to the emergency room, according to the search warrant, which was first reported by the Wisconsin State Journal.

Jason Sidener is the former executive director of the Democratic Party of Wisconsin.

Jason Sidener is the former executive director of the Democratic Party of Wisconsin.

Democratic Party of Wisconsin

Sidener told a police officer he had picked up Allen, whom he described as a friend, the night before at a hotel. He said they smoked marijuana and he went to bed between 1 and 2 a.m.

He told the officer he woke up around 5 a.m. and that Allen was “breathing really weird and her body was like a pile of mush.” He said he monitored her for about an hour, then carried her to his truck and drove her to the emergency room.

The medical examiner’s office found Allen had died of an overdose. She had heroin, fentanyl, another drug like fentanyl and cocainein her system.

Officers turned up text messages between Sidener and Allen starting on Sept. 9 in which Sidener said he was doing the “hard stuff” and would bring the “hard.” Allen told Sidener she believed she could control herself because she had been sober, according to the search warrant.

The search of Sidener’s condominium and vehicle turned up four guns; six drug pipes; Oxycodone, Adderall and other pills; suspected marijuana; suspected crack cocaine; needles and other drug paraphernalia; two digital scales; and a ledger and notebook with names and dollar amounts in it.

Breianna Hasenzahl-Reeder, a friend and Democratic Party co-worker of Sidener’s, told an officer she believed Sidener had been using opiates because he would disappear for long periods during the work day, nod out during meetings and at times appear incoherent.

She said Sidener had recently been fired from the Democratic Party, but did not say exactly when that happened.

Fentanyl, which can be more than 50 times as powerful as heroin, has been linked to a growing number of deaths in Wisconsin and around the country. Used to treat chronic pain, it is also used by drug dealers to spike heroin and other opioids, producing a lethal combination.

"It's no surprise to me that fentanyl analogs were found in a recent overdose death. The morbid prediction is that more and more people will die with fentanyl analogs in their system," said Rep. Joel Kleefisch (R-Oconomowoc), who's working to ban these substances.

Kleefisch has a proposal, Assembly Bill 335, that seeks to ensure that drug dealers will not be able to avoid prosecution simply by tweaking the chemical structure of fentanyl to produce a similar drug known as an analog.

In the case involving Cassandra Nygren, Delain, the Brown County chief deputy, said Nygren and her fiance, Shawn M. Gray, 33, were arrested in connection with the recent overdose death of an unnamed victim.

Nygren had spent two years in state prison for heroin possession following a near-fatal overdose. After her release in June 2014, she became Marinette “street team coordinator” for Rise Together, a state group that tries to educate and mentor young addicts.

Nygren and her father shared her story with the Milwaukee Journal Sentinel and other news outlets as John Nygren worked in the Legislature on a series of bills addressing heroin and opiate abuse.

Cassandra Nygren was convicted again in 2015 of drug possession. That time, she was admitted to Brown County Drug Court, a program started in 2009 to help participants fight addiction through phases of treatment, testing and supervision.

She participated successfully from September 2015 through March 2016, when she was sent to jail for a month for an undisclosed infraction of drug court rules.

In 2014 Phil Drewiske, then age 24, was a recovering heroin addict from Hudson. He started using prescription drugs in middle school. At 16 he was injecting heroin. His father was a key to his recovery.

Mike De Sisti/Milwaukee Journal Sentinel

A key part of John Nygren’s legislative work has been ensuring that an anti-overdose drug known as Narcan is available to more first responders and that state laws encourage those present for an overdose to call for help. Those measures are meant to prevent overdose deaths.

In a statement Wednesday, John Nygren offered his prayers for the victim in his daughter's case and for his own child.

"There are no words that we as a family can offer to give any real comfort for the tragic loss," Nygren said. “This is just another example, in a seemingly endless line, of the disastrous and destructive consequences addiction continues to have on families and communities nationwide. These stories are the motivating factor behind all our work in the Legislature to fight this epidemic."